Feb 18, 2021
Provided you’re a cartridge—and not looking at a mirror—short and fat are in. The technical advantages are genuine. Quicker and more uniform ignition because of better access to the primer flame and a more uniform burning curve. These are conducive to accuracy, but that’s hard to measure because quality of barrel and uniformity of ammunition. are much more important to accuracy than cartridge design.
There are physical advantages that can readily be seen. Because of better burn of propellant, there is an energy increase per grain of propellant. Also, because of more efficient burning, shorter, wider cartridges tend to produce full velocity in shorter barrels than cartridges with longer and relatively slimmer cases. From a hunter’s standpoint, the fat little fireplug-shaped cartridges we call short magnums also fit in shorter actions. These, in turn offer genuine advantages. Less overall gun weight, shorter and faster bolt throw, and shorter actions are more rigid, also conducive to accuracy.
None of this is new. Starting in 1998, in the space of a few years the market was asked to embrace about 11 short (and short-action, super-short and compact) magnums from major manufacturers. I’ve messed with all of them and all do what they are supposed to do. However, to my thinking this was a whole bunch all at once. Some have already suffered an early demise. We, the jury, are still out on others. Without question, the most popular of the bunch has been the .300 Winchester Short Magnum (WSM), probably followed by the .270 WSM.